A 33-year-old Wisconsin woman died in July and dozens of others in the state have suffered severe bleeding from rat poison since March, when it started showing up in products that mimic marijuana, often called K2 and spice.

Health officials say they don't know how or why rat poison got into the products, which they call synthetic cannabinoids because they don't contain real marijuana. They're sold in convenience stores and online, often marketed as incense and labeled "not for consumption."

At least 40 cases of bleeding from rat poison have been confirmed in Milwaukee, Outagamie, Dane and Rock counties since March. The outbreak has appeared in 10 other states this year, including seven deaths. Illinois was hit the hardest, with Wisconsin and Maryland next in line.

Wisconsin officials reported Saturday there have been eight new cases in the past two weeks, suggesting the outbreak isn't over.

"We really can’t predict what’s going to happen," said Dr. Jon Meiman, chief medical officer of the state health department. "If anyone has used these products, they need to talk to their physician."

The rat poison reduces vitamin K in the body, which is responsible for helping blood to clot in healthy ways. Without it, there can be heavy internal and external bleeding, from bruises to coughing up blood.

The outbreak sheds light on an evolving industry that continues to tweak drug molecules to skirt government regulations, keeping users and health officials guessing about what's actually in them.

According to the Wisconsin Department of Justice, some of the cannabinoids have been banned but laws can't keep up with the changing formulas.

When state agencies sued two stores for selling the products, Attorney General Brad Schimel said they had to use "creative thinking" to bring civil charges against the stores for false advertising.

What are synthetic cannabinoids?

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At least one person in Illinois has died from synthetic marijuana, and doctors say it may be because of rat poison, according to the Chicago Tribune. Veuer's Sam Berman has the full story.
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In 2008, chemist John Huffman started getting calls from concerned parents and officials about a drug he'd designed at Clemson University in South Carolina: JWH-018. It was a cannabinoid with similar properties to THC, the psychoactive agent in marijuana.

The drug was starting to turn up in products that were marketed as incense but were being used like marijuana. Huffman's published research had been "hijacked," according to a study he co-authored. He'd meant to help create a painkiller for the medical setting.

In response to the products, lawmakers started banning JWH-018 and similar chemicals. Manufacturers tweaked their recipes, spraying new mystery substances onto herbs. Now, experts know less about what's in them.

"When JWH was taken directly from medical research, there was at least some knowledge of what these molecules were," said Stefanie Jones, who does education and outreach for the Drug Policy Alliance. "We are getting further and further away from substances we know anything about."

The drugs don't come with a list of ingredients. Often they're made abroad.

"These drugs are not regulated in any way so we often don’t know what chemicals are involved," Meiman said.

The drugs have caused health problems since their launch. But health officials say rat poison, or brodifacoum, never showed up in these products until this year.

Experts including scientists at the Centers for Disease Control and Prevention say it's unclear how or why rat poison got into the mix.

Why do people use these products?

Experts and users say the appeal of synthetic cannabinoids are their price, availability, and the fact that they don't show up on routine drug tests.

One Milwaukee woman, now 27, said she used K2 when she was 18 because her employer conducted random drug tests. USA TODAY NETWORK-Wisconsincontacted her through a Facebook group, and she asked to remain anonymous.

"I wasn't a drinker, I didn't wanna do anything harder than weed, so I went to the legal version," she said.

She soon ended up in a hospital for a combination of effects from K2 and dehydration, she said.

"We learned our lesson and now I stick to actual cannabis, and I believe it should be legal," she said. "Even if I'm 27 now and know better, those 16-year-olds don't."

Even without rat poison, synthetic cannabinoids can cause sickness, rapid heart rate, confusion and hallucinations. The molecules take a stronger grip on cell receptors than the THC in marijuana and are more dangerous.

How can we stop these products from killing people?

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Emergency crews responded to dozens of people vomiting and passing out in a downtown park in New Haven, Connecticut. Police say laced synthetic marijuana could be the culprit.
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At the CDC, where staff members are helping to investigate the Midwest outbreak, Tegan Boehmer said the main focus is educating the public about the dangers of the product.

"Because they're easy to obtain, there’s a perception that they’re safe and legal, neither of which are true," Boehmer said.

Meawhile, the drugs seem to be getting more dangerous. Boehmer said that although there have been health problems since the drugs first hit the market, research shows there are more potent products out now.

"There’s also the danger of having multiple synthetic cannabinoids in the same product and not knowing how they’ll interact," she said.

Boehmer said she couldn't comment on how states should address the problem legislatively.

Some researchers posit that regulations will probably never catch up to manufacturers, who can keep changing their compounds.

The Drug Policy Alliance, a nonprofit that advocates for harm-reducing public policy, suggests one answer could be legalizing and regulating actual marijuana — an approach drug designer Huffman himself has advocated for.

"It was the limitations on drugs that are most popularly used that drove this proliferation of synthetic analogs to begin with," said Jones, from the Drug Policy Alliance. "You'll find there aren’t outbreaks like this happening in states where marijuana is legal."